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Well, it seems the back and forth of N54 tuning horsepower records is over... for now. Earlier this month Vargas Turbo Tech and Pro Tuning Freaks (with a Cobb flash) set the N54 hosrepower record at 693 wheel horsepower. That basically obliterated what anyone else had hit on this platform. A competing tuner with a single turbo (the Vargas VTX63 upgrade consists of twin turbos) N54 upgrade kit out of nowhere pulled out suspect numbers that eeked out a few more wheel horsepower.

This became an ego pissing match of sorts but Vargas and Pro Tuning Freaks went back to the dyno to make some adjustments and managed to surprisingly quickly and easily take the horsepower record right back (and where it rightfully belongs due to the breakthrough being thanks to the Vargas work with the High Pressure Fuel Pump) with a 725 wheel horsepower pull.

A video is included below along with two graphs. The E92 335i is equipped with a Pro Tuning Freaks pro tuning using the Cobb flash system, 109 octane race gas, meth injection, and of course the Vargas Turbo Technologies VTX-R 63 (GTX2863R) twin turbo upgrade and HPFP upgrade.

Congratulations to Vargas, PTF, and Cobb for pushing the platform into new territory.

The car that flows more air in and out will go faster, all other things constant. This is really all you need, and there are no discrepancies analyzing this vs. the contrary.ST cars are not much, if ANY faster than RB cars , so theories and data from tuners is inconsistent in real-world results

You shouldn't have to make excuses for a kit, the numbers, track times, etc should speak for themselves....the ST has been anything but impressive IMO. Its not something I'd pay money for that's for sure.

You ever heard of the term "Dyno Queen"? Just because the data & dyno numbers are there, there are NO guarantees that the data + dyno sheet will translate into real world, usable power.

Dyno data is directly derived from the acceleration data on the rollers. One gear pull on the rollers and one gear pull on the street should match nicely. This is why virtual data works as far as the parameters are right and road is level. 60-130mph has just one shift typically meaning no chances to screw much. So it relates quite well with the dyno. A lot of turbo power together with slow spool does not guarantee nice ETs because the outcome is dependent on other factors. Especially 6MT N54s with a lot of power have high variance in 1/4. So, dyno figures translate into performance only in cases where the external variables can be controlled.

Dyno data is directly derived from the acceleration data on the rollers. One gear pull on the rollers and one gear pull on the street should match nicely. This is why virtual data works as far as the parameters are right and road is level. 60-130mph has just one shift typically meaning no chances to screw much. So it relates quite well with the dyno. A lot of turbo power together with slow spool does not guarantee nice ETs because the outcome is dependent on other factors. Especially 6MT N54s with a lot of power have high variance in 1/4. So, dyno figures translate into performance only in cases where the external variables can be controlled.

Taking performance #s off a dyno will give you a "baseline", but it certainly shouldn't be taken as the best, most accurate performance measurement. Here are my 3 biggest problems of using a dyno to measure acceleration :

The problems with dynos is 99% of the dynos used are not wheel hub dynos, which likely will mean there is a less than 100% traction between the wheels & roller. Also, not only can tire size impact values on a dyno, but tire compound can alter results (article posted on the PTF Blog going into further detail).

The stress on the drivetrain (especially an AWD car) is significantly higher on a dyno then it is on the road, specifically because of the resistance. Naturally this will impact your times.

What kind of dynos are we talking about -- Inertia vs. Load. Even besides that, if the dyno operates with a fluid, the longer duration of the pulls, the viscosity of the hydrolic fluid often changes altering the results (Higher temperature = Less viscosity = Less resistance = "Better" results).No matter what road you're on, the resistance between the tires & pavement is a constant + won't change (resistance doesn't decrease as you continue the pull, aiding in acceleration).

With most 60-130 results, people come "rolling" through 60 (60 isn't the "starting" speed), so at that point the are in the optimal accelerating gear & have already built up boost (if FI'd). We also need to remember that 1st & foremost, dynos are a tuning tool and you should take performance numbers with a grain of salt because of the lack of consistency from one dyno to another. Yes, I know that acceleration should be constant regardless of what dyno you're on, but there's no way to guarantee that.

Bottom line, 60-130 times are a combination of showcasing area under the curve + gearing, and you're never going to accurately simulate road conditions on a dyno.

Taking performance #s off a dyno will give you a "baseline", but it certainly shouldn't be taken as the best, most accurate performance measurement. Here are my 3 biggest problems of using a dyno to measure acceleration :

The problems with dynos is 99% of the dynos used are not wheel hub dynos, which likely will mean there is a less than 100% traction between the wheels & roller. Also, not only can tire size impact values on a dyno, but tire compound can alter results (article posted on the PTF Blog going into further detail).

The stress on the drivetrain (especially an AWD car) is significantly higher on a dyno then it is on the road, specifically because of the resistance. Naturally this will impact your times.

What kind of dynos are we talking about -- Inertia vs. Load. Even besides that, if the dyno operates with a fluid, the longer duration of the pulls, the viscosity of the hydrolic fluid often changes altering the results (Higher temperature = Less viscosity = Less resistance = "Better" results).No matter what road you're on, the resistance between the tires & pavement is a constant + won't change (resistance doesn't decrease as you continue the pull, aiding in acceleration).

With most 60-130 results, people come "rolling" through 60 (60 isn't the "starting" speed), so at that point the are in the optimal accelerating gear & have already built up boost (if FI'd). We also need to remember that 1st & foremost, dynos are a tuning tool and you should take performance numbers with a grain of salt because of the lack of consistency from one dyno to another. Yes, I know that acceleration should be constant regardless of what dyno you're on, but there's no way to guarantee that.

Bottom line, 60-130 times are a combination of showcasing area under the curve + gearing, and you're never going to accurately simulate road conditions on a dyno.

While most of this is true, there are similar amount of more crucial uncontrollable variables in the real world. There are uphills, downhills, head wind, tail wind and most of the factors you mentioned above have an impact in the street as well, traction, tyre compound etc etc.

There is no perfect data from any one point that can represent the performance in the real world.

While most of this is true, there are similar amount of more crucial uncontrollable variables in the real world. There are uphills, downhills, head wind, tail wind and most of the factors you mentioned above have an impact in the street as well, traction, tyre compound etc etc.

There is no perfect data from any one point that can represent the performance in the real world.

Agreed but 60-130 and 1/4 mile times/traps are at least data collected in the "real world" with someone driving the car on the road, not on rollers with a big fan

Agreed but 60-130 and 1/4 mile times/traps are at least data collected in the "real world" with someone driving the car on the road, not on rollers with a big fan

They are like different sports. Some compete with dyno figures, others with 1/4 and both are nice to follow even for those who won't attend in these sports. For me the real world measure is the lap time at the local track. Different sports require different things, for dyno sports you do engine and turbo modding and tuning, for 1/4 you do some more stuff other than the power only and driver is a factor as well, for racing it is a lot about the driver skill and even less about the car. However, the car is a major element also in the latter sports. On the other hand, lap time is also the most covering performance measure of a car. It's about the power, suspension aerodynamics, brakes etc.